"That's something we never imagined when she started racing," trainer John Shirreffs said of Zenyatta possibly matching the legendary filly. "And then as she has continued to win, it became something that was maybe possible. And now we're on the brink of it. So it's very exciting."

The crowd favorite will meet many of the same rivals in the 1 1/16-mile Pro-Ride event that she has defeated in her three earlier victories this year, with one significant addition among the eight entrants. That is Godolphin's Cocoa Beach, who ran second to Zenyatta in last year's Breeders' Cup Ladies' Classic (gr. I) and is shipping west to get accustomed for a second try at the World Championships.

The Lady's Secret is the last of four of Breeders' Cup Challenge races on the Santa Anita program, with the earner automatically qualifying for the $2 million Ladies' Classic Nov. 6 over the same track. Zenyatta, though, might end up taking on males a day later in the $5 million Breeders' Cup Classic (gr. I) regardless of whether she wins the Lady's Secret.

And it will be no cakewalk. Zenyatta very nearly lost her perfect record in her last start, the Clement L. Hirsch (gr. I) at Del Mar Aug. 9, making her customary late charge barely in time to register a head victory over Anabaa's Creation, an unheralded mare from the Julio Canani barn that returns in the Lady's Secret.

Also in the field from that race is Lethal Heat, who set soft fractions in the Hirsch and nearly got away with stealing it before finishing a close third, and Zenyatta's stablemate Life Is Sweet, who gets back on her favorite surface after running fourth in the 1 1/16-mile Hirsch.

Zenyatta won last year's Lady's Secret by 3 1/2 lengths as a 7-10 choice leading up to her smashing Breeders' Cup win and subsequent honors as the nation's top older female. This year, though, hasn't gone quite as smoothly, as the stunning 5-year-old Street Cry mare's campaign was delayed by bad weather in Kentucky and marked by significant gaps between races. She won the Milady (gr. II) and Vanity (gr. I) handicaps at Hollywood Park this spring and has been off since capturing the Hirsch.

"Last year she had such a great campaign when she kept beating grade one winners, grade one winners on and on and on," Shirreffs said. "This year she didn't have the chance to develop slowly. She had to jump in and face Life Is Sweet in the Milady.

"They had the side door closed so she had to come out the back (to win by 1 3/4 lengths). And then her second race (the Vanity), which is the race that a lot of horses have a tendency to bounce coming off a long layoff, and she gets 129 pounds and still was able to win. So third race down, at Del Mar and they go :13 and change the first three quarters and she's trailing the field and somehow just fires an unbelievable last quarter and catches the field. So she does things that just ordinary horses can't do."

Three-for-three over the Santa Anita main track, Zenyatta has earned $2,594,580 for owners Jerry and Ann Moss. Shirreffs said a decision on which way they will head for the Breeders' Cup would be made after the Lady's Secret.

"They've already given Rachel Alexandra Horse of the Year," Shirreffs noted, which would weigh against going against males. He added, "I personally think that the horse comes first. The titles and the awards are great but always the horse comes first."

Shirreffs also said that it's possible that Zenyatta could still run after the Breeders' Cup, meaning it's possible she could still meet the super filly Rachel Alexandra, whose connections refuse to run her on Santa Anita's synthetic track.

"I think probably if everything goes well and Zenyatta is okay," he said of that possibility. "How far she goes -- how many races she runs after that I don't know because of breeding season. But there is always a possibility."

Zenyatta, to be handled once again by Mike Smith, drew post 5. Under weight-for-age conditions, she will carry 123 pounds, equal to the rest of the field except for the 3-year-old Sweet and Flawless, who carries 120. Zenyatta, who will be seeking her seventh grade I win, has been the odds-on choice in her last eight races.

After her big runner-up effort in last year's Ladies' Classic, Cocoa Beach won last fall's Matriarch (gr. IT) on the Hollywood Park grass before returning to New York for trainer Saeed bi Suroor. In a limited 2009 campaign, she won a minor stakes on the lawn at Saratoga before running fourth in the Ballston Spa Handicap (gr. IIT) on a soft Saratoga turf course Aug. 29. The 5-year-old Chilean bred's only prior start on a synthetic track was in the Breeder's Cup.

Cocoa Beach won the Beldame (gr. I) at Belmont over a sloppy track last year. Richard Migliore takes over riding chores, replacing Ramon Dominguez. They break from the rail.

Prestonwood Farm's Irish-bred Anabaa’s Creation was making her third start in the United States after being imported from France when she nearly upset Zenyatta in the Hirsch. No other filly or mare has come closer than the 5-year-old bay who was making her second start over synthetics following an allowance race victory at Santa Anita on April 2 in her U.S. debut.

With jockey Tyler Baze riding out of town, Rafael Bejarano inherits the mount in the Lady’s Secret.

Lethal Heat, most recently second in the Cal Cup Classic for trainer Barry Abrams, could very well get the same sort of pace scenario that made her so dangerous in the Hirsch. The presence of grade II winner Briecat and the big outsider Made for Magic could make the fractions a little more honest, however.

Life Is Sweet returns to the track where she won the El Encino (gr. II), La Canada (gr. II) and Santa Margarita Handicap (gr. I) consecutively earlier this year for Shirreffs. The trainer said he would have preferred to give the 4-year-old Storm Cat filly a start on turf rather than face Zenyatta for a third time, but that Martin Wygod, who owns her along with his wife Pam, thought she would run better at Santa Anita than she did on Del Mar's Polytrack.